Jan, it is not only a joke sentence but also an insult to the victim and encouragement to all those scum who rob and thieve, burgle by distraction or aggression, defraud and con the elderly and vulnerable. This mockery of justice tells all the ne'er-do-wells that their worst punishment will be having to appear in court. So, they are in a win-win position should the almost impossible happen that they get caught in the first place.
I would have thought that common sense would demand that they face charges of theft, obtaining money by deception and money laundering. The police should try to obtain evidence of them living beyond their means and use the proceeds of crime to get the victim's money back, or at least some of it.
A sentence of 5 years (of which they would serve 30 months, probably) might start to persuade them and their ilk that robbing and cheating the vulnerable isn't worth it.

Where I come from, all jewellers are routinely granted a firearms certificate that allows them to carry a concealed pistol, or to keep one on their business premises or at their home.

All banks there have armed rentacops, and airport style scanning for any person entering.

That lady would have dealt with those robbers in record time had this country allowed her to exercise the same degree of self defence, but no: the only armed people here are a small number of cops, and those belonging to the criminal fraternity.